(a) Field of the Invention
This invention relates to a print paper feeding device for photograph processing apparatus wherein a printer and processer are combined with each other to continuously make printing and development in series.
(b) Description of the Prior Art
In such photograph processing apparatus as is mentioned above, generally a long tape-shaped paper is used as a print paper. Such tape-shaped print paper is temporarily stopped in the printing section of the printer to carry out a predetermined printing operation, is then intermittently fed out by one picture frame and is moved toward the processor but the print paper fed into the processor is continuously moved at a predetermined velocity. Thus, in this kind of photograph processing apparatus, the tape-shaped print paper is subjected to run intermittently in the front half of the entire course but to run continuously in the rear half. In order to secure the smooth running of the print paper in spite of such contradiction in the running state, the average running velocity of the paper to be intermittently fed out of the printer is so selected so to be higher than the running velocity within the processer so that the printed paper will be stocked within a stocker provided within the printer and a loop will be formed within the stocker. Further, in this kind of photograph processing apparatus, even if the printing operation is interrupted and the paper is no longer fed out of the printer, the paper fed into the processer will have to be made to run continuously at a predetermined velocity. Therefore, when the amount of the printed paper stocked within the stocker becomes smaller than a predetermined value, that is to say, when the size of the loop within the stocker becomes smaller than a predetermined value, in order to prevent the paper from breaking, it will be necessary to properly cut the paper between the stocker and processer. Further, also in case the amount of the paper fed out of the printer into the processer exceeds a fixed value predetermined in response to the processing capacity of the processer, in order to prevent various troubles from being caused by the loosening of the paper within the processer, it will be necessary to properly cut the paper between the stocker and processer.
Now, such paper must be cut without stopping the operation of the processer. However, in fact, when the paper is cut with a cutter, at least the paper portion to be cut will have to be stopped. Further, the paper must be cut between the picture frames.
In order to meet the above mentioned various requirements, a loop of the paper may be formed between the cutter and processer so that, when the cutter operates, the feeding roller means used to pull the paper out of the stocker will be stopped and the paper will be cut before the above mentioned loop is eliminated. In such case, the feeding roller means will be stopped when a cut mark made in advance on the paper coincides with the position of the blade of the cutter. Further, it is necessary that the above mentioned loop should be always kept to be of a fixed size while the long paper is conveyed. That is to say, if this loop is too small, before the cutting operation of the cutter ends, the paper will begin to move and will be cut in a position displaced from the cut mark and, as a result, an accident of cutting the photograph will be caused. If this loop is too large, the space occupied by the loop will be too large to be desirable.
In order to always keep the size of the loop constant, the feeding velocities of the feeding roller means for pulling out the paper stocked within the above mentioned stocker and the feeding roller means for feeding the paper into the processer may be accurately tuned with each other in the formation. However, such formation is very difficult, because the influence of errors accumulated in the course of feeding the long paper can not be avoided.